Ruby模块化编程示例2

subtotal = 100.00
taxrate = 0.175
tax = subtotal * taxrate
puts "Tax on $#{subtotal} is $#{tax}, so grand total is $#{subtotal+tax}"
module MyModule
  REWARD = 100

  def prize
    return "You've won #{REWARD} credits"
  end

end
def MyModule.lose
  return "Sorry, you didn't win"
end
puts(MyModule.lose)

Tax on $100.0 is $17.5, so grand total is $117.5
Sorry, you didn't win

module MyModule
  GOODMOOD = "happy"
  BADMOOD = "grumpy"

  def greet
    return "I'm #{GOODMOOD}. How are you?"
  end
  def MyModule.greet
    return "I'm #{BADMOOD}. How are you?"
  end
end
puts(MyModule.greet)

I'm grumpy. How are you?

class Thing
  def initialize( aName, aDescription )
    @name = aName
    @description = aDescription
    puts("Thing.initialize: #{self.inspect}\n\n")
  end

  def aMethod( aNewName )
    @name = aNewName
    puts("Thing.aMethod: #{self.inspect}\n\n")
  end
end
class Thing2 < Thing
  def initialize( aName, aDescription )
    super
    @fulldescription = "This is #{@name}, which is #{@description}"
    puts("Thing2.initialize: #{self.inspect}\n\n")
  end

  def aMethod( aNewName, aNewDescription )
    super( aNewName )
    puts("Thing2.aMethod: #{self.inspect}\n\n")
  end
end
class Thing3 < Thing2
  def initialize( aName, aDescription, aValue )
    super( aName, aDescription )
    @value = aValue
    puts("Thing3.initialize: #{self.inspect}\n\n")
  end
  def aMethod( aNewName, aNewDescription, aNewValue )
    super( aNewName, aNewDescription )
    @value = aNewValue
    puts("Thing3.aMethod: #{self.inspect}\n\n")
  end
end
class Thing4 < Thing3
  def aMethod
    puts("Thing4.aMethod: #{self.inspect}\n\n")
  end
end
class Thing5 < Thing4
end
ch = Thing2.new('google','baidu')
ch.aMethod('google','baidu')

Thing.initialize: #<Thing2:0x000000000652e558 @name="google", @description="baidu">

Thing2.initialize: #<Thing2:0x000000000652e558 @name="google", @description="baidu", @fulldescription="This is google, which is baidu">

Thing.aMethod: #<Thing2:0x000000000652e558 @name="google", @description="baidu", @fulldescription="This is google, which is baidu">

Thing2.aMethod: #<Thing2:0x000000000652e558 @name="google", @description="baidu", @fulldescription="This is google, which is baidu">